Oppai

my omp lines are somewhat yellowed but not at all brittle or cracked. I was planning to just put them back in.

DaleClark

iTrader: (55)

Give them a good flexing, especially on the engine side near where they go around the injectors. If they are good you are good. I think they don't have a lot of mileage on them, usually about 80-100k miles and they snap easily.

If they flex around good you are good. Once they are installed they are static, they only break if you mess with them and if they are brittle.

Dale

Oppai

Found the culprit of my bad gas...
On the bright side engine is in the car now and ready for fluids.

DaveW

Yup - that'd do it.

Oppai

There are absolutely zero options in NYC right now for disposing of old gas without paying HUGE fees for private companies to take it...
Do you folks think it's safe to cut this yellowed gas 50/50 with new gas in my dailies? Take it easy in the dailies for a tank and ride it out...
the newer cars should have ECU's better prepared to deal with knock yeah?

Pete_89T2

iTrader: (4)

You probably can get away with doing that, but I wouldn't - it would suck to have your daily driver go down over crappy gas. Any possibility someone might buy the yellowed gas from you as-is? Perhaps it's good enough for use in outdoor power equipment, like lawn mowers, generators, etc.

TwinCharged RX7

iTrader: (14)

I'd throw small bits of it into the daily. A gallon at a time with almost a full tank.

Oppai

Good news: Car is back on the road and more or less running.

Got away with using up the bad gas in my daily with no problems.

Have spent almost all of my free time for over 2 months working on this car and chasing gremlins...

Bad news:
The latest gremlin is high(?) oil temp on the brand new motor. As seen below, the car reads 220f (+20f over the water temp) when stopped at a red light.


Once the car moves, the temp comes down promptly but it will settle at about 220f when stopped. The temp is being taken from a sandwich plate at the oil filter pedestal.

The sensor and gauge being used is for all intents and purposes identical to the water temp sensor/gauge so the likelihood of a bad reading is relatively low.
I've read on other threads on the forum that 210 is about the upper threshold of acceptable oil temps on a hot day-- it was 68f today here. For context, the driving was city driving in NYC-- never exceeded 35mph and lots of red lights and traffic.

A part of me wants to say I'm being paranoid but I just want to be overly thorough considering the time, money, and sweat I've put into this thing... Is this oil temp reading on a fresh motor something I should be looking into?

The vacuum at idle is also reading low-- 13mmhg at idle when warmed up.
The only mod i've done that might affect the vacuum pressure is a secondary throttle plate delete, but I don't think that would be enough to take it from 20mmhg to 13mmhg..
Idle settles at about 850-900 rpm and occasionally will randomly jump to about 1100-1200 when stopped.
Could my high oil temps be related to the low vacuum pressure at idle?-- Lean burn caused by vacuum leak?

Testrun

My opinion is paranoia on the temps. Mine will hit 220 sitting in traffic on a hot day. Another reason why I switched to synthetic after break in as it ran 5-10° cooler. This is on an 80+ day.
Which ecu are you running? I forgot sorry.

Oppai

Running a stock n3a7 ECU.
castrol GTX 20w50 for engine break-in

DaleClark

iTrader: (55)

Back up a step or two - what did you do for the engine? Rebuild? Swap in a new block? Any porting done?

Do you have single or dual oil coolers? Did you have that oil temp gauge on the old engine?

New engines can have low-is vacuum until they're broken in, they will improve compression (and hence idle vacuum) as they get miles on them.

Dale

Oppai

Full swap of a fresh brand new engine from Ray Crowe.
No porting done at all. The way it came out of the mazda factory is the way it went in.
Dual factory oil coolers in series. Only 20 ish miles on the car so far.
Oil temp gauge, along with all the other gauges are brand new glowshift brand gauges.

Testrun

Give it a few k miles. I got mine from Ray also. Had Kilo swap seals and port it. Took a couple k to get into the 14s at idle I think.... that's around 850 rpms. At 900ish or around 1000 rpms I think it's in the mid/high 16s? I can't remember right now.....
I should run a compression just for the hell of it.
I know the few old school guys that have been around it and heard it start say "wow, that's a strong motor". Sometimes that re assuring enough.

I would not sweat it.. Ray said he has heard awesome things about these new motors recently...

Oppai

Seeing my car with everything open in the driveway as I chase down gremlins has been a familiar sight this year.. Hope to have her fully sorted soon.
Thanks for the input, I will drive her and keep one eye glued on the gauges. Hopefully the temps don't continue to creep beyond 220.

DaleClark

iTrader: (55)

May be worth checking, when the car is warm, that both oil coolers are hot. If you have one or both that aren't hot it could be a problem with the thermostat in the oil cooler. Not common but it will take 2 seconds to test and be a good thing for peace of mind.

I don't know how hard I'd trust the output of those Glowshift gauges, that is about as cheap as a gauge can get.

Also, with that front bumper, make sure you have good ducting to the oil coolers. If air just goes around them instead of through you will miss out on a lot of cooling.

Dale

Oppai

Got it, will check oil cooler temps.
Once the car gets moving I bleed oil temp extremely fast-- I watch the needle climb down 1 degree per second or more going around 25mph, and it settles at a temp +/- 5 degrees of the water temp while the car is moving.
Makes me think the car is generating extra heat at idle and not necessarily that the oil coolers aren't doing their job.

As far as ducting it's definitely suboptimal but now that you mention it, I'll definitely have to fab up something for the coolers

Oppai

Took her out on a 15 mile, 1 hr shakedown. (Obviously still taking it real easy on the throttle for break in)
Oil temp peaked at 223, water temp peaked at 206. It was about 82 out.

Car is happy to idle at 800rpm with AC off, but the AC on will drag my idle into the depths of hell until the car refuses to stay on. If the car idles buttery smooth at 800rpm with my ~13-15mmhg vacuum, does that rule out vacuum leaks? or should I still smoke test my vacuum system?
I bent the line going into the AC dryer can when reinstalling the IC ducting. Could the restriction in the pinched bend be causing elevated load on the AC compressor-- thus poor idling characteristics?

The only way I can get the car to stay on is to set the engine idle to like 1900, where turning the AC on drags it down to about 1200.
The idle in this state also tends to go up and down randomly, but quite frequently. Like the ECU is confused or something about the idle.
It's possible that the elevated(?) AC load is causing my moderately elevated oil temps in traffic too due to the wonky idle condition. Most of my test drives have been with AC on at least part of the time.

Oppai

By the way, as a disclaimer, I did do some due diligence doing some searches for AC idle issues.
Came up with possible culprits according to forum threads--
clutch switch -- doesn't seem to match my symptoms
BAC valve -- I had previously already cleaned and tested my BAC valve. I will double check again but I asked first about the pinched drier line because I didn't think the BAC valve was likely to be the issue since I had cleaned it (And also used the ac) not too long ago prior to blowing the engine.

DaveW

When I used to drive my FD home from work in the summer 90+F heat, at idle (waiting for lights, etc.) the AC compressor would cycle off and on every minute or less due to the car not moving fast enough to cool stuff off even with the fans running. I think that's what you're having, so the idle air control is not working as it should. Therefore it's not raising the idle to handle the AC compressor load.

Oppai

Gah, so I probably have a complete failure of that idle air control valve since I've already cleaned it prior.
Guess that silly thing just opened up a $300 sized hole in my pocket..

I saw some ford model BAC valves that look very similar in size and flange-- was wondering is by some chance they might be cross compatible?

DaveW

There's also the effect of the relatively low vacuum due to the engine just starting to break in. The marginal compression, especially at low revs, would exacerbate the low idle/stalling when the AC kicks in w/o the IAC raising the idle speed.

Oppai

Dave, do you also think that the low vacuum is due to the fresh engine?
In my conversations with Rich (GoodFellasFd3s) he seems very convinced that I have one or more issues with the car causing low vacuum in spite of my steady 800rpm idle.
Has me a bit nervous about driving the car frankly.

I do have a rotarycompressiontester unit on the way so hopefully that will ease my paranoia.

DaveW

I don't pretend to be an expert on all things FD. However, it just makes good sense that especially with the rotary engines' known sensitivity to low compression, until it is fully broken in it will be more sensitive to extra load at idle speed. So if the IAC is not working properly, it also makes good sense that you'd have the issue you're describing.

IMO, there is nothing about your idle vacuum or this issue that says to me there's something seriously wrong. So fix the IAC issue and wait several hundred miles until you come to any conclusions that the engine has a problem.

If the compression tester shows that the compression is getting better with mileage, and that all faces read pretty equal, you should be in good shape.

DaveW

My ~75 K-mile FD has about 16-17 mmhg vacuum at 750 RPM, and there's nothing wrong with it. It runs perfectly. As I said, wait a bit and let it break in.

Oppai

Thanks so much Dave!

Took the IAC/BAC valve out and it looked clean but was sticking, might have been on the shaft out of view.
Threw at it every solvent under the sun until giving it 12v power would actuate it quickly and reliably every time. Threw it back in-- works like a charm now.
Car still has a tendency to drop revs LOW if I free rev and let off the throttle with AC full blast, but for the most part it stays on now.
And thank you for the words of reassurance about the vaccum pressure-- really helps me trust the car now to put it through its paces and start putting some real break in miles on it.

Frankly I should have checked this first having already encountered an idle issue with this valve once before on the old engine.
Shouldn't have let my arrogance stop me from triple checking things...